Polk Audio F/XiA4 Timbre-Matched Bipole/Dipole Surround Loudspeakers - Pair (Black)

Model: FXIA4BLK UPC: 747192118518 Item: 156262


Regular Price: $399.00

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754 Route 309 (Bethlehem Pike) Montgomeryville, PA 18936
  • Mon: 9:30am - 8pm
  • Tues - Fri: 9:30am - 6pm
  • Sat: 9:30am - 5pm
  • Sun: 12:00pm - 5pm
(215) 368-8343
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38 Greenfield Avenue, Ardmore, PA 19003
  • Mon- Fri: 11am - 6pm
  • Sat: 10am - 5pm
  • Sun: Closed
(610) 649-7002
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Full Fidelity and High Performance

The F/XiA4's engine is the dual Dynamic Balance 1" dome tweeter design and a 5 1/4" Dynamic Balance driver that produces believable real-life effects at prodigious volumes. The selectable bipole/dipole function allows you to configure it to your space and 7.1 systems, and the smaller cabinet enables it to fit in more places.


  • The trapezoidal shaped cabinets aim the drivers and tweeters in opposing directions to produce a more realistically diffused wavefront and wide, lifelike imaging of surround sound.
  • With the flip of a switch, Polk's dipole/bipole circuitry changes the sound-field from direct to indirect radiation patterns enabling you to place the surround speaker beside or behind you, depending on your listening room setup.
  • Klippel motor optimization uses laser measurement technology to ensure a smooth excursion path at either end of the volume spectrum for uniform performance at both low and high volumes.
  • Polk's proprietary, patented Dynamic Balance technology allows their engineers to design out distortion-causing driver and system resonances, so you only hear the good sounds.
  • Durable, computer-modeled, injection-molded butyl rubber surrounds suppress unwanted cone resonances for a life-time of reliable sound.
  • The F/XiA Cascade Tapered Crossover eliminates the comb filtering and beaming, common to multi-driver speakers, which degrades the quality of the audio and collapses the sound-stage.
  • Patented Acoustic Resonance Control (ARC) technology suppresses cabinet resonance that causes distortion to ensure clear and natural sound.
  • Computer-modeled anti-diffraction grilles enhance the good looks while minimizing sonic interference.
  • All Polk loudspeakers are timbre-matched within their series, designed with the same components throughout, to achieve seamless speaker-to-speaker blending effects in multi-channel systems.
  • Gold-plated, professional-style 5-way binding posts offer the most secure connection options.



  • Dimensions (W x H x D): 11.375" x 12" x 7.437"
  • Weight: 9 lbs.
  • Driver complement: (1) 5.25" diameter mid/woofer, (2) 1" diameter tweeter
  • Total frequency response: 50Hz - 27kHz
  • Lower and upper -3dB limits: 60Hz - 26kHz
  • Recommended amplifier power per channel: 20 watts - 150 watts


What's in the Box

What's in the Box:

  • F/XiA4 Timbre-Matched Bipole/Dipole Surround Loudspeakers - Pair



Customer Reviews for Polk Audio F/XiA4 Timbre-Matched Bipole/Dipole Surround Loudspeakers - Pair (Black)

5.0 / 5.0
5 Reviews
5 Stars
4 Stars
3 Stars
2 Stars
1 Star
April 13, 2019
10 months ago
Versitle, substantial surround speakers
I have been using the RTI A1s as side surrounds. Then the FXI A4s caught my eye. I have them placed off to the left and right sides of my couch on studs in the rear wall. The woofer/midrange and tweeters aim across my couch at a 45 degree angles. These speakers are very substantial and similar to the A1s in sound with the same 5.25" mid/woofer and the same 1" tweeter(s). I am using them in direct mode. They weigh about 3 lbs less than the A1s and are a little easier to mount on the wall and do not stick out as far as the A1s. They sound great! I have my side surrounds set as "small" and crossed over at 80 hertz.

Along with the A1s, they make doing 5.1 or 7.1 surround in a 180 sq ft living room very practical. Yet they are REAL speakers, not the ultra budget 5.1 in a box type of a system. I have the RTI A5 small towers as my fronts along with the CSI A6. I am considering downsizing the center to the CSI A4. I have had a Yamaha Aventage 2060 since August 2017 and got a new 50" flat screen last September. Life is good!!

The RTI line of speakers is a royal hoot! I recently watched a BD of Deep Water Horizon in 5.1 that is also coded for Atmos and was nearly blown away. My A1s may soon be installed as front overhead/atmos speakers. Yamaha already has audio processing for non Atmos front overhead effects. Maybe Atmos will catch on and stick around.

I definitely recommend the Polk Audio FXI A4s.
November 7, 2018
1 year ago
Excellent product sold by an excellent company.
February 21, 2018
over 2 years ago
These speakers don’t just complete my 7:1 home theater system but give movies and music a seamless sound experience. Two thumbs up! The esthetics of these Polk Audio’s as they hang on the wall look like a work of art but with attitude, powerful sound for surrounds!
January 9, 2018
amazing sounding
I bought the tsx550t towers the tsx250c and two sets of tsx220 as well as four polk 12" subs (psw505) running off a Yamaha rxv773. It sounds unbelievable. I listened to a lot of brands be for I bought and you can not touch this polk setup without spending twice as much.
February 21, 2014
Originally posted at
Polk Audio


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Why did you choose this?
World Wide Stereo Store
Need middle surround speakers to go with my new Denon Receiver from WWS, these match my rear surrounds.
Barry A on Nov 3, 2019
Need a good set of rear speakers to complete my 7.1 setup. Good reviews and the price was a determining factor.
Michael J on Mar 26, 2018
Need middle surround speakers to go with my new Denon Receiver from WWS, these match my rear surrounds.
Barry A on Nov 3, 2019
Its good ...
Benjamin J on May 5, 2019
Need a good set of rear speakers to complete my 7.1 setup. Good reviews and the price was a determining factor.
Michael J on Mar 26, 2018
Its good ...
Benjamin J on May 5, 2019